youtube.com (youtu.be) - playlists are also supported
vimeo.com
rutube.ru — it is recommended to use the URL from the embed code
vk.com (vkontakte.ru) — the URL from the embed code is required
facebook.com
metacafe.com
clipfish.de
veevr.com
video.mail.ru
smotri.com
video.qip.ru
video.google.com
video.yandex.ru — the URL from the embed code is required
video.bigmir.net
tvigle.ru — the URL from the embed code is required
video.online.ua
video.sibnet.ru
yapfiles.ru

URLs do not need to be cleaned from the garbage arguments as our [video] will work it out. You can use both the URL of the video page and the URL of the embed code (unless other instructions are given).

So this means you no longer have to post the exact Youtube URL. IT can contain https:// or &featured or any of the other nonsense that somehow sneaks into the URL!